Hydrocarbon conversion catalysts



United States atentO 2,871,200 HYDROCARBON CONVERSION CATALYSTS 'Thomas F. Doumani, Whittier, Calif., assignor to Union Oil Company of California, Los Angeles, Calif., a v corporation of California N Drawing. Application August 22, 1955 Serial No. 529,937

7 Claims. (Cl. 252-440) This invention relates generally'to catalysts and catalytic processes for the conversion of hydrocarbons and hydrocarbon mixtures.- More particularly this invention relates to new and improved methods for the preparation of molybdenum-containing catalysts and especially to the incorporation of certain metal sulfates in molybdenum catalysts for use in the catalytic conversion of hydrocarbons in the presence of hydrogen.

Catalysts for the high temperature catalytic conver-' sion of hydrocarbons should generally lay down a minimum of carbonaceous deposits .on the catalyst during reaction. The formation of "catalytic coke is undesirable since it generally leads to decreased liquid recov: eries, unnecessary consumption and/or contamination of the recycle hydrogen stream and to short on-stream reaction cycles between regenerations. Molybdenum ox- ;ide catalysts are particularly. prone to lay down large ;amounts of carbon during conversions and consequently -molybdenum oxide catalysts. require frequent regenera-. tion. Molybdenum sulfide catalysts also suffer this disadvantage but to a lesser degree. The withdrawal of- .catalysts from reaction for purposes of regeneration .contributes to decreased throughput of feed stock per unit volume of catalyst and often entails extensive cycle systems for frequent periodic-regeneration.

It has been found that the inclusion of sulfate such ras metal sulfate in molybdenum catalysts increases the :selectivity of the catalyst for the desired reactions. It has also been found that the activity of the molybdenum sulfate type catalyst can be increased by impregnation with inorganic halogen-containing acids. The effect of the halogen acid is obtained when either the catalyst is impregnated or when the carrier is impregnated with the acid.

It is therefore, an object of this invention to provide molybdenum-containing catalysts for the catalytic con version of hydrocarbons which produce a minimum oi carbon deposition and a minimum of destructive hydrogenation.

It is another object of this invention to promote supported molybdenum catalysts for use in "hydrocarbon conversion reactions vso as to increase the hydrogen production and decrease carbon lay down on the catalyst.

It is another object of this inventi'onto provide-a process for the catalytic upgrading of gasoline in the presence of supported molybdenum catalysts promoted with certain metal sulfates. I

It is another object of this invention to *pi'omotef cobalt molybdate type catalysts with certian metal sulfates so as to decrease splitting reactions and increase hydrogenation and dehydrogenation reactions.

It is another object of this invention to promote molybdenum catalysts with sulfates and inorganic'halo gen containing acids. h v

Other objects and advantages of this invention will become apparent to those skilled in the art as the description thereof proceeds.

Briefly this invention relates to the preparation and use of molybdenum containing supported catalysts whi h 2,87L200 Patented Jan. 27, 11359 are promoted with certain metallic sulfates wherein the presence of the sulfate moderates the destructive hydrogenation characteristics of the molybdenum catalyst.

Such catalysts may or may not contain added metal oxides such as cobalt oxide, iron oxide, nickel oxide, copper oxide, zinc oxide, cadmium oxide and the like, or sulfides of any of the foregoing metals in-addition to the metallic sulfate.

The metal oxides and/or sulfides of metals which may be incorporated with molybdenum oxides and/ or sulfides and promoted with metal sulfates or metal sulfates and inorganic halogen-containing acids include the oxides and/or sulfides of metals, having an atomic number of or greater than 22 and particularly those metals having an atomic number in the group 22 to 58.

The metal sulfates which are most generally useful are those of divalent metals having an atomic number of '22 or more and particularly those metals having an atomic numberin the group 22 to 58. As examples of metal sulfates which exert a promoting action, the following may be employed: titanium, vanadium, chromium, manganese, iron, cobalt, nickel, copper, zinc, strontium, zirconium, ruthenium, rhodium, palladium, silver, cadmium, tin, barium, cerium, platinum, thorium and uranium. Ammonium sulfate and sulfuric acid may s also be employed to introduce sulfate into molybdenum catalysts; The sulfates of the three divalent metals of atomic number less than 22, i. e. beryllium, magnesium and calcium, are useful also, especially in catalysts to be employed for dehydrogenation reactions.

The molybdenum and the metal sulfate may be in-- corporated into the catalyst in a number of ways such as impregnation, coprecipitation, mixing of the hydrous gels or precipitation in the presence of a hydrous gel. Thus molybdenum'oxides and/or sulfides may be coprecipitated with a carrier such as alumina and the sulfate thereafter incorporated either by precipitation therewith or by impregnation. In the preferred method of catalyst preparation the molybdenum is supported on the carrier by impregnation and the metal sulfate, provided such sulfate is soluble, is also introduced into the carrier by impregnation. In one modification of the invention the molybdenum and the metal sulfate may be simultaneously introduced by coimpregnation.

The carriers which are suitable for distending molybdenum and metal sulfates according to the process of this invention include ferric oxide, stannic oxide, alumina, silica, zirconia, thoria, magnesia, magnesium hydrox'ide, titania and the like, or combinations of these. The preferred carrier is an activated gel type alumina and particularly an alumina gel containing about 1 to 15% by weight of silica and preferably between about 3 and 8% by weight of silica. The presence of the small amount of silica in the alumina serves to stabilize the resultingcatalyst and prolongs the catalyst life as is described in U. S. Patent 2,437,532 to H. C. Huffman.

Prior to the impregnation steps, the carrier is normally shaped into the physical form desired for the catalyst. For this purpose the dried carrier is usually ground, mixed with a lubricant such as graphite or hydrogenated vegetable oil, and pilled. In the activation of the carrier by heating the lubricant is removed by combustion. Alternatively the carrier may be used in granular form, or it may be ground into powder, made into a paste and extruded. Where the catalyst is to be employed in a fluidized process, such as in fluidized desulfurization, denitrogenation, and the like, the carrier is formed into a finely divided state as in microbead form, or it is ground into a fine state and is there- .after impregnated. In the case of fluidized processes the 3 carrier can be impregnated in larger form, e. g., granules, pills, etc, and thereafter ground to the desired powder size for the processing.

In the preferred method ofcatalyst preparation the molybdenum together wrih any additional metal oxides is impregnated on the car-rier prior to impregnation with the metal sulfate. In other modifications of the invention however, the metal sulfate may bedeposited either before or during the impregnation of the molybdenum oxide, sulfide or other compound as Well as after. Where the catalyst is further promoted with a halo-gem containing acid, such acid may also be impregnated either before, during matter the impregnation of the molybdenum and/or metal sulfate. Where coprecipitation or the like is employed for the deposition of molybdenum and/or other metal oxides or sulfides the metal sulfate is preferably impregnated on such catalyst after drying and after sufficient heating to render the cata lyst adsorbent. I

In the preparation of a carrier and/or a carrier containing molybdenum and/or other metal oxides or sulfides and/or inorganic halogen-containing acids for impregnation, the carrier is heated to a temperature sufficient to render it adsorbent for the impregnation step. Normally such heating is effected for two to six hours at 600 F. to 1200 F. for example. Activation temperatures as low as about 300 F. may be employed without difficulty however. Following the activation the carrier is cooled and is thereafter immersed in tbeappropriate impregnation solution.

The molybdenum-containing impregnation solution is preferably ammoniacal ammonium molybdate although aqueous solutions of other soluble molybdenum compounds may be employed. ln the preferred method, ammonium paramolybdate is dissolved in about 14% aqueous ammonia and the resulting mixture is diluted with distilled water or with more diluted aqueous ammonia toform a clear ammonium molybdatesolution of the desired concentration. The concentration of the ammonium molybdate solution will depend on the particular carrier being employed and on the desired concentration of molybdenum in the finished catalyst. Where alumina or alumina-silica carriers are employed, and a finished catalyst comprising between about 6% to 16% of M is desired, the molybdenum-containing impregnation solutions will have a concentration of molybdenum ranging from about 12 to 32 grams of MoO 100 ml.

Molybdenum-containing impregnation solutions may be prepared from other soluble molybdenum salts. Thus an ammonium sulfo-molybdate solution may be prepared by dissolving ammonium molybdate in an ammonium sulfide solution. The molybdenum obtained by impregnation with such solution is obtained as a molybdenum sulfide after heating to remove the ainmonia.

Other metal salts may be impregnated either before, after or With the molybdenum. in one modification of the invention the molybdenum and cobalt may be combined and deposited on the carrier according to the method described in U. S. Patent 2,486,361 to Paul G. Nahin. The preferred metal oxides and/or sulfides for use in conjunction With molybdenum oxide or sulfide include the oxides and/or sulfides of iron, nickel and cobalt. Of these materials the cobalt oxide is preferred.

The cobalt-containing impregnation solution is preferably an aqueous solution of cobaltous nitrate althoughother water-soluble compounds of cobalt. may be employed. Thus cobalt chloride and cobalt sulfate may.

be employed in the impregnation solutions. The concentration of the cobalt-containing impregnation solution will depend upon the carrier being employed and the desired concentration of cobalt in thefinished catalyst. Where alumina or alumina-silica carriers are employed and where a final catalyst composition contain 4 ing from about 2% to 10% by weight of C00 is desired, the concentration of the cobalt impregnation solution will range from about 4 to 23 grams of (300/ 100 ml.

In the impregnation of the carrier the activated carrier is immersed in the impregnation solution for a short time such as between about two minutes and minutes for example. A more uniform impregnation is obtaincd withlonger impregnation periods.

A-fter immersion in the impregnation solution a part of the impregnation solution is adsorbed by the carrier and the excess solution is thereafter removed. The impregnated carrier after draining and drying in a low temperature. oven such as at 180 F. to 230' R, for example, is finally activated by heating to a temperature of 600 F. to 1000" F. for two to six hours. The final activation may be carried out by bringing the dried impregnated carrier to the required reaction temperature.

in the case where multiple impregnations are an ployed such as for the incorporation of other metal oxides and/or inorganic halogen-containing acids in addition to the molybdenum, any component may be deposited first and the impregnated carrier after drying is reactivated as described hereinbefore for the subsequent impregnation of the remaining component and/or components.

Many of the metallic sulfates which are useful in this invention are Water-soluble and accordingly the impregnation solution may be prepared by dissolving the appropriate metal sulfate in water. The concentration of the metal sulfate solution will depend upon the particular carrier being employed and the desired concentrations of the metal and sulfate in the finished catalyst. Where a finished catalyst comprising between about 1% and 25% of the metal sulfate is desired, the impregnation solution will contain between about 2 and 60 grams of metal sulfate per 100 ml. of solution.

The molybdenum-sulfate type catalysts of. thisinvention with or without other metal oxides and/or sulfides may be further promoted by impregnation of either the carrier or the catalyst with anwinorganic halogen-containing acid. The acid may be impregnated before, during or after the impregnation of any of the other components. Preferably the acid is impregnated on the finished catalyst containing the molybdenum and the sulfate however.

The acid impregnation solution according to the method of this invention may be prepared from fluorinecontaining inorganic acids such as hydrofluoric acid, fluorosulfonic acid and fluorosilicic acid and the like. Where chlorine-containing acids are employed, hydrochloric acid, chlorosulfonic acid and the like may be employed.

In general the fluorine or chlorine retained by the carrier varies directly with the concentration of the impregnating solution. With the use of alumina carriers it has been found that the preparation of catalysts containing between 0.2% and 5% by weight of fluorine or chlorine required impregnating solutions contaniing be- 'tween about 0.4 and 10.4 grams of fluorine (as F) or chlorine (as Cl) per 100 ml. of solution.

While other concentrations of fluorine or chlorine may sometimes be employed, we generally employ between about 0.05% and 5% of fluorine orhlorine and I we prefer to employ between about 0.2% and 3% of fluorine or chlorine based upon the finished catalyst.

In the simplest modification of the invention the carrier or the carrier supporting the molybdenum is impregnated with an aqueous metal sulfate. However in other modifications of the invention derivatives of metal sulfates such as double salts with organic compounds and/ or basic sulfates of metals may be employed. Double salts of metal sulfate include compounds, of nickel sulfate for example with varying amounts of ammonia, hydrazine, hydroxyl. amine and the like may be employed. Basic sulfates which have the elements of asneoo pregnation solutions containing a metal sulfate and nitrate wherein the metal nitrate is preferentially decomposed to the oxide by heating at low temperatures such as above 400 F.

While catalysts prepared by the method of this invention may be prepared which contain different percentages of the metal sulfate, those containing between about 1% and 35% and preferably between about 3% and 20% by weight are most generally employed. Although the impregnation method described hereinbefore is the pre ferred method, other methods may be employed such as.

coprecipitation, copilling and the like. Thus, a hydrous alumina gel may be mixed with an aqueous solution of nickel sulfate or other water-soluble metal sulfate for example and the mixture dried at 200 to 300 F. for example to obtain the finished catalyst. In other methods of preparation a hydrogel of nickel oxide or sulfide with alumina may be prepared, dried, and the adsorbent material impregnated with sulfuric acid to convert a part of the nickel to nickel sulfate for example.

The finished catalyst is useful for effecting various hydrocarbon conversion reactions such as desulfurization, denitrogenation, hydrogenation, hydroforming, reforming, cracking, destructive hydrogenation and the like. The hydrocarbon conversion may be effected at temperatures between about 500 F. and 1500" F. and preferably in the presence of hydrogen. During usage varying amounts of deposits comprising mostly carbon, nitrogen and sulfur compounds accumulate on the catalyst and are periodfically removed by regeneration. Regeneration is effected by passing air diluted with flue gas, steam, nitrogen or other inert gas over the catalyst to combust the deposits while maintaining the temperature of the catalyst between 800" F. and 1050 F. The combustion is completed in the presence of undiluted air while maintaining the temperature of the catalyst between 800 F. and 1050 F. The regenerated catalyst after reduction with hydrogen has practically the same catalytic activity as the freshly prepared catalyst even after a large number of regenerations.

When the catalyst is employed for high sulfur stocks such as those containing between about 0.5% and 4.0% by weight of sulfur, there is some tendency for the catalyst to decline in activity, which decline seems to result from the slow build-up of sulfur on the catalyst. When the regeneration gases contain steam in excess of 5% and preferably in excess of 15% by volume, the rate of catalyst decline with successive regenerations is considerably lessened.

In certain cases such as when high sulfur stocks are being employed as the feed stock, water may be added to the feed to minimize sulfiding of the catalyst. Usually the added water will amount to between about 0.5 and 10 volume percent of the feed.

For the purpose of desulfurizing petroleum stocks, shale distillates and the like, the catalyst of this invention is employed under the following conditions: reaction temperatures between about 600 F. to 1000 F., pressures between about atmospheric to 5000 lbs. per sq. in. or more and at space velocities between about 0.2 and 10.0 volumes of liquid feed stock per volume of catalyst per hour, and 500 to 10,000 cu. ft. of added hydrogen per barrel of feed. The particular set of conditions is determined by the stock to be desulfurized and by the nature of the product desired.

The catalyst in this invention can also be employed for denitrogenation of such stocks as coal tar distillates, shale oils and heavy petroleum distillates whereby up to 99% of the nitrogen and substantially 100% of the sulfur can be removed simultaneously. For denitrogenation of such stocks the following conditions are employed: reaction temperaturesbetween about 700? and 1000 F.,

pressures between about 500 and 10,000 lbs per iii, 2 feed rates between about 0.2 and 10.0 volumes of liquid feed stock per volume of catalyst per hour, and about 1,000 to 10,000 cu. ft. of added hydrogen per barrel of feed. For the removal of nitrogen it is generally de-l tions the maximum efliciency for removing nitrogen from the stocks is obtained.

The catalysts of this invention may also be employed for the process generally termed hydroforming, which process serves to reform a gasoline range hydrocarbon stock and increase its aromatic content. stocks for the purpose of reforming and increasing their aromaticity, the following conditions are employed: reaction temperatures between about 800 to 1200 F., pressures between about 50 to 1000 lbs. per sq. in., space velocities between about 0.2 and 4.0 volumes of liquid feed stock per volume of catalyst per hour, and about 1,000 to 10,000 cu. ft. of added hydrogen per barrel of feed. The specific conditions are determined by the nature of the specific feed stock employed and the quality 30% and preferably between about 6% and 12% by weight of M00 or MoS The additional metal oxides and/ or sulfides such as those of cobalt, nickel, iron and the like'are employed generally in a concentration of about 0.5% and 15% and preferably between about 1.5%

and 10% by weight. The metal sulfates are generally em-; ployed in the concentration between about 0.5% and- 20% and preferably in the range of about 1.5% and 10%.

When inorganic halogen-containing acids are employed as additional promoters, the catalyst normally contains between about 0.05% and 5% and preferably between about 0.2% and 3% of fluorine or chlorine. In certain cases higher concentrations may be employed if desired.

Perhaps the process of this invention is best illustrated by the following specific examples.

Example I An alumina-silica gel containing an estimated A1 0 and 5% SiO was prepared by the coprecipitation of an aqueous mixture of sodium aluminate and sodium silicate with carbon dioxide. The precipitate was washed until substantially free of sodium ions, dried at 200 to 230 F. and activated by heating for two hours at 1000 F. A solution of ammonium molybdate was prepared by dissolving about 1607 parts by weight of ammonium paramolybdate, assaying about 81% by weight of M00 in about 1940 parts by weight of 28% aqueous ammonia and about 1550 parts by weight of distilled water. About 4400 parts by weight of the activated gel were immersed in the ammoniacal solution of ammonium molybdate, drained, dried and heated at 1100 F. for about two hours. An aqueous solution of cobalt nitrate was prepared by dissolving about 1466 parts by weight of cobalt v nitrate heXa-hydrate in about 2000 parts by weight of water. The carrier supporting the molybdic oxide was then immersed in the cobalt nitratesolution, drained,

For processing dried and activated by heating to 1100 F. for two hours. The catalyst prepared by this method contained about 8.6% M and 3.0% CoO.

'l.he.foregoing composition containing cobalt oxidemolybdenum oxide on thesilica-alumina carrier was then divided into a series of samples each of which was impregnated with a different metal sulfate so as to produce a catalyst containing about 0.0166 mol of metal sulfate per 100 grams of catalyst. In each case the metal sulfate impregnation solution was prepared by dissolving the appropriate metal sulfate or metal sulfate hydrate thereof in distilled water in an amount calculated to give the desired concentration. Each of the catalysts was drained of excess impregnation solution after about minutes of impregnation time, dried and brought to the reaction temperature. Each of .the catalysts was then tested under the following reaction conditions:

Temperature, F; 900 Pressure, p. s. i. 450 Process time, hours 4 Liquid hourly space velocity 2.0 Hydrogen addition, cu. ft./barrel of feed 5000 For testing these catalysts gasoline stock boiling sulfstantially in the range of between 200 F. and 400 F. obtained by distillation of a California crude was employed. The gasoline contained about 12% aromatics v and had an Fl clear octane rating of 66 which increased to 78 upon the addition of 3 ml. of tetracthyl lead fluid.

The following data were obtained on the reaction prodnets of the several catalysts tested:

. Inorganic Sulfate Research 00- Gas Make, Liquid tanc Rating cu. ft./bbl. Yield, Vol. Weight, Percent Plus 3 Formula Percent of feed Clear ml. H2 C1-C2 TEL Example 11 In another series of experiments the cobalt oxidemolybdenum oxide catalyst of Example I was impregnated with nickel sulfate to form a series of catalysts of varying NiSO content. These catalysts were tested with the feed stock of Example I under the conditions described therein. The following data were obtained:

Research Gas Make, Liquid Octane Rating cu. ftJbbl.

Yield, N 1804, Percent by-Wcight Volume Percent Plus of Feed Clear 3 ml. Ha C -C3 TEL Marked Hydrocracking 90. 4 85. 0 95. 0 566 156 92. 5 84. 5 9S. 0 650 128 95. 0 S2. 5 94. 0 472 135 95. 3 78. 0 91. 5 382 03 Example 111 In another series of experiments the cobalt oxide molybdenum oxide catalyst of Example I was impregmated with cobalt sulfate to form a series of catalysts of varying C080 content. These catalysts were then tested with the feed stock of Example I under the conditions described therein. The following data were obtained:

Marked hydrocracking occurred The extreme hydroeracking activity of the cobalt oxidemolybdenum oxide catalyst is partly moderated with the impregnation of only 0.1% by weight of CoSO and the reaction becomes endothermic and substantially a dehydrogenation reaction upon the impregnation of about 0.5 or more percent by weight of 0050 Example I V A molybdenum oxide-alumina catalyst was preparedby immersing the alumina-silica carrier of Example I in an ammoniacal ammonium-molybdate solution prepared according to the method of Example I, draining, drying Research Gas Make, N iSO4 Liquid Octane Rating cu. ft./bbl. Percent Yield, Run Number by Vol.

Weight Percent Plus of feed Clear 3 ml. H2 C1-C3 TEL 0.0 88. 9 88. 5 98.0 342 211 2. 46 92. 8 87. 5 97. 5 518 209 B 2. 46 96. 4 87. 5 97. 0 588 230 b 2. d5 87. 5 90. 0 99. 0 514 281 c 2. 46 92. 5 86. 0 5 504 d 2. 46 87. 2 87. 5 97. 5 510 225 1 0 2. 46 93. 7 81. 5 94. 5 372 181 8 Regenerated catalyst from run 2. b Rcgcnerated catalyst from run 3. Regenerated catalyst from run 4 using 4.0 space velocity. Regenerated catalyst from run 5 using 4.0 space velocity. 9 Regenerated catalyst from run 6 using 6.0 space velocity.

Example V The molybdic oxide-alumina catalyst of Example IV I was impregnated with 6.0% by weight of C050 and when tested according to the method described in Example I the following data were obtained:

Research Gas Make, N10, NiSO4, Liquid Octane Rating cu. ft./bb1. Percent Percent Yield,

by by Vol. Weight Weight Percent Plus of feed Clear 3 m1. H2 C1-C3 TEL Example VII An ammoniacal ammonium molybdate solution is poured into a solution of aluminum nitrate causing the precipitation of a mixed hydrogel of alumina and molybdic oxide. The hydrogel contains about by weight of M00 on an anhydrous basis. The hydrogel is filtered, washed by resuspension of the precipitate in distilled water, dried and crushed to form granules. The dried hydrogel is heated to about 300 F. to render it sufliciently adsorptive for impregnation. A portion of the granules was immersed in a 2% aqueous solution of sulfuric acid, drained and again dried at 300 F. When the two catalysts, the one impregnated with sulfuric acid and the other unsulfated, are compared under the test conditions of Example I it is found that the sulfated catalyst is more selective for dehydrogenation and gives a higher liquid recovery.

Example VIII The dried mixed hydrogel of molybdic oxide and the alumina of Example VII is impregnated with a 5% by weight solution of cupric sulfate. The finished catalyst contains about 2.2% by weight of copper sulfate and when tested under the conditions of Example I is found to be more selective for dehydrogenation than is the corresponding molybdena alumina without impregnation with copper sulfate.

Example IX In another series of experiments the nickel sulfatemolybdenum oxide-alumina catalyst of Example IV and the nickel oxide-nickel sulfate-molybdenum oxidealumina catalyst of Example VI were separately impregnated by immersion in a 2% solution of hydrofluoric acid. After draining, drying at 300 F. and testing under the conditions of Example I, it is found that the added hydrofluoric acid improves the liquid product in each case. Similar results are obtained when the copper sulfate-cobalt oxide-molybdenum oxide-alumina catalyst of Example I is impregnated with a 5% solution of hydrochloric acid.

EXAMPLE X A molybdenum sulfide catalyst is prepared by impregnating the silica-alumina carrier of Example I with an ammoniacal solution containing 2% ammonium sulfide and 10% by weight of ammonium para-molybdate (81% M00 After draining and drying at 300 F. in a nitrogen atmosphere the molybdenum sulfide-aluminasilica catalyst is impregnated by immersion in a 4.5% by Weight aqueous solution of cobalt sulfate. The catalyst containing the cobalt sulfate is superior to a corresponding catalyst prepared substituting cobalt nitrate for the cobalt sulfate when the two are tested under the conditions of Example I.

In broad aspect this invention relates to a new catalyst for the catalytic conversion of hydrocarbon stocks in the presence of hydrogen. The molybdenum catalysts of this invention which are promoted with metallic sulfates have good stability and show high activity for the desired reactions with low activity for reactions producing carbon and low boiling hydrocarbon gases such as methane. The mobybdenum catalysts may employ molybdenum sulfides or oxides with or without other metal oxides. Such catalysts may be promoted by inclusion of inorganic halogen containing acids by impregnation so as to improve additionally the character of the products obtained.

This application is a continuation-in-part of application Serial No. 235,579, filed July 6, 1951, now U. S. Patent No. 2,748,062.

The foregoing disclosure of this invention is not to be considered as limiting since many variations may be made by those skilled in the art without departing from the spirit or scope of the following claims.

I claim:

1. A hydrocarbon conversion catalyst consisting essentially of a major proportion of an adsorbent carrier which is essentially activated alumina, and intimately distributed therein between about 4% and 30% by weight of molybdenum oxide, between about 0.5% and 15% by weight of an oxide of a metal selected from the group consisting of cobalt and nickel, and between about 0.5 and 20% by weight of a sulfate of a divalent metal having an atomic number between 4 and 5 8 inclusive.

2. A catalyst as defined in claim 1 wherein said carrier is an intimate mixture of 85% to 99% alumina gel and 1% to 15 silica gel by weight.

3. A catalyst as defined in claim 1 wherein said metal sulfate is copper sulfate.

4. A catalyst as defined in claim 1 wherein said metal sulfate is nickel sulfate.

5. A catalyst as defined in claim 1 wherein said metal sulfate is iron sulfate.

6. A catalyst as defined in claim 1 wherein said metal sulfate is cadmium sulfate.

7. A catalyst as defined in claim 1 wherein said metal sulfate is cobalt sulfate.

References Cited in the file of this patent UNITED STATES PATENTS 2,206,377 Weiss July 2, 1940 2,325,033 Byrns July 27, 1943 2,592,016 Engel Apr. 8, 1952 2,687,370 Hendricks Aug. 24, 1954 2,732,329 Doumani Jan. 24, 1956 FOREIGN PATENTS 643,862 Great Britain Sept. 27, 1950 

1. A HYDROCARBON CONVERSION CATALYST CONSISTING ESSENTIALLY OF MAJOR PROPORTION OF AN ADSORBENT CARRIER WHICH IS ESSENTIALLY ACTIVATED ALUMINA AND INTIMATELY DISTRIBUTED THERIN BETWEEN ABOUT 4% AND 30% BY WEIGHT OF MOLYBDENUM OXIDE OF A METAL SELECTED FROM THE GROUP WEIGHT OF AN OXIDE OF A METAL SELECTED FROM THE GROUP CONSISTING OF COBALT AND NICKEL, AND BETWEEN ABOUT 0.5% AND 20% BY WEIGHT OF A SULFATE OF A DIVALENT METAL HAVING AN ATOMIC NUMBER BETWEEN 4 AND 58 INCLUSIVE. 